Step-by-step explanation:
1) Radius = Half of Diameter
[tex]r = \frac{1}{2} d \\ r = \frac{1}{2} \times 9 \\ = 4.5cm[/tex]
2) Given r = 4 in.
Circumference of Circle =
[tex]2\pi \: r \\ = 2\pi(4) \\ = 8\pi \: cm[/tex]
3) Given r = 5 in.
Area of Circle =
[tex]\pi {r}^{2} \\ = \pi {5}^{2} \\ = 25\pi {cm}^{2} [/tex]
4)Diameter = 2x Radius
[tex]d = 2r \\ = 2 \times 6.5 \\ = 13cm[/tex]
Note for questions 2 and 3 I will leave answers in terms of pi as the question did not specify to leave the answer as what. You can use your calculator to evaluate them if needed.
